A Dodge Grand Caravan weighs between 3,500 and 4,000 pounds depending on the configuration. This is a popular model of minivan used to transport up to 7 passengers.
The 1984 Dodge Caravan which was the first year had a curb weight of 2,910 lbs with manual transmission and 2,954 lbs with an A/T.
A Grand Caravan does not have a timing belt.
About 6000 pounds
Dodge Caravan SE curb weight (lbs): 3763.3
Depends on what minivan you are asking about. You do not say. Here are curb weights for a few minivans (2013 model year): Dodge grand caravan 4510 pounds, Nissan quest 4371 pounds, Toyota sienna 4310 pounds. You can find these numbers by going to the manufacturer's websites. For most vehicles they give curb weights, but not all. Curb weight means including fuel, oil, coolant, etc. but not people or cargo.
About 120 pounds
Depending on the make/model/ trim, usually 1.8-2.2 tons.